1. Field of Invention
The present invention relates to a composition for a flexible substrate. More particularly, the present invention relates to a composition for a flexible substrate having anti-yellowing and heat-resistant properties and a flexible substrate formed by the same.
2. Description of Related Art
In recent years, organic polymers materials have been widely applied in various electrical elements or devices for increasing various properties (for example, electrical insulation, heat resistance, mechanical properties and so on). Among those polymers, polyimide polymer is the most commonly applied in related industries due to its excellently mechanical and electrical properties.
WO 2009/107429 discloses a polyimide precursor composition for transparent flexible substrate. The polyimide precursor is formed by reacting diamine (comprising fluorene-containing benzidine and 1,4-cyclohexyldiamine) and tetracarboxylic dianhydride. The aforementioned composition is used to form a flexible substrate with high transparency. However, during the process of heating the polyimide precursor, the cured and formed polyimide has yellowing problem under high temperatures so that such polyimide cannot satisfy the requirement of this industrial field.
Therefore, there is a need to provide a composition for a flexible substrate and flexible substrate, so as to improving the aforementioned disadvantages of the prior composition and flexible substrate.